Which part contains the fractions in ascending order?
Aptitude
Decimal Fraction
Difficulty: Medium
Choose an option
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A$$\frac{11}{14}, \frac{16}{19}, \frac{19}{21}$$
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B$$\frac{16}{19}, \frac{11}{14}, \frac{19}{21}$$
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C$$\frac{16}{19}, \frac{19}{21}, \frac{11}{14}$$
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D$$\frac{19}{21}, \frac{11}{14}, \frac{16}{19}$$
Answer
Correct Answer: $$\frac{11}{14}, \frac{16}{19}, \frac{19}{21}$$
Explanation
### Concept & Strategy
To arrange fractions in ascending order (smallest to largest), either convert them into decimal values or analyze the numerical gap between their numerators and denominators.
### Step-by-Step Solution
Let's evaluate the approximate decimal value for each unique fraction:
* $$\frac{11}{14} \approx 0.785$$
* $$\frac{16}{19} \approx 0.842$$
* $$\frac{19}{21} \approx 0.904$$
Comparing the resulting decimal values:
$$0.785 < 0.842 < 0.904$$
Mapping these back to the original fractions:
$$\frac{11}{14} < \frac{16}{19} < \frac{19}{21}$$
### Exam Strategy & Shortcut
**Numerator-Denominator Gap Analysis:** Find the difference between the denominator and numerator for each fraction:
* For $$\frac{11}{14}$$, the gap is $$3$$.
* For $$\frac{16}{19}$$, the gap is $$3$$.
* For $$\frac{19}{21}$$, the gap is $$2$$.
When the gap is the same (as with $$\frac{11}{14}$$ and $$\frac{16}{19}$$), the fraction with larger numbers is greater. Thus, $$\frac{16}{19} > \frac{11}{14}$$.
When comparing fractions with similar numbers, a smaller gap (like $$2$$ for $$\frac{19}{21}$$) generally indicates a fraction closer to $$1$$. Thus, $$\frac{19}{21}$$ is the largest.
The correct ascending sequence is $$\frac{11}{14}, \frac{16}{19}, \frac{19}{21}$$.
### Common Pitfall
Miscalculating decimal values during long division, especially with prime denominators like $$19$$. Using the gap analysis shortcut saves time and reduces calculation errors.
### Final Answer
**Therefore, the correct answer is option (a).**